Optimize performance: eliminate N+1 queries, parallelize bulk operations, add early exits

[Copilot]

Identified and resolved critical performance bottlenecks in lock management operations that cause unnecessary database load and sequential processing delays.

Changes

1. N+1 Query Elimination in GetLockOverviewAsync

Batch-fetch all users in a single query instead of per-lock iteration:

// Before: N database queries
foreach (var conLock in contentLocks) {
    var user = await _userService.GetAsync(conLock.UserKey);  // Query per lock
}

// After: 1 database query + dictionary lookup
var userKeys = contentLocks.Select(x => x.UserKey).Distinct().ToArray();
var users = await _userService.GetAsync(userKeys);
var userLookup = users.ToDictionary(u => u.Key, u => u.Name ?? "Unknown");

Impact: 100 locks = 100 queries → 1 query (99% reduction)

2. Parallel Bulk Unlock in BulkUnlockAsync

Process independent unlock operations concurrently:

// Before: Sequential execution
foreach (var key in keys) {
    await _contentLockService.UnlockContentAsync(key, userKey);
}

// After: Parallel execution
var tasks = keys.Select(key => _contentLockService.UnlockContentAsync(key, userKey));
await Task.WhenAll(tasks);

Impact: 10 operations × 100ms = 1000ms → ~100ms (10x faster)

3. Early Exit Guards in Notification Handlers

Skip database queries when no items require lock checking:

if (deletingContentKeys.Count == 0) return;
var allLocks = await _contentLockService.GetLockOverviewAsync();

4. Code Clarity

Separated Attempt<int>.Result property access into explicit variable to eliminate confusion with async Task.Result blocking.

Files Changed

• ContentLock/Services/ContentLockService.cs - N+1 query fix
• ContentLock/Controllers/ContentLockApiController.cs - parallel bulk unlock
• ContentLock/Notifications/*.cs - early exit guards (2 files)

All changes are backward compatible with no API surface modifications.

Original prompt

Identify and suggest improvements to slow or inefficient code

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